Firefall is a fairly fun game. It's free to play; microtransactions are present, but for the most part you can get items off the Cash Shop (Red Bean Store) with currency earned in game. It's a first person/third person shooter with jumpjets. The game world is interesting if you are into the sci-fi genre. I started playing when it game finally released a month or two ago, and I'm still enjoying myself. I haven't spent a penny on the game, yet I've unlocked almost all the advanced frames within that time frame. Also, the gunplay isn't too bad, only annoying thing is sometimes the enemy's movements are a bit off/unpredictable/laggy, but that could be due to my horrid wireless connection.
I'll end my gibbering with a pros vs cons list.
+Interesting Sci-fi world with vast room to expand (both lore/story-wise and game content-wise)
+Third/First person shooter
+Free to Play with not alot of Pay to Win content (A Bike/LGV is great for running around, but I believe you can get one early on now, instead of waiting to level a frame to 25)
+Cash shop items can be bought with in-game currency.
+5 base frames with different playstyles mixed in with a fair number of advanced frames to change it up.
+Customization of your character is free to a point (some hairstyles/accessories cost cash shop currency, but you can always change the way your character looks whenever you want)
-Not a huge amount of things to do once you've hit max level (level 40 right now)
-Glitches/bugs can sometimes be an issue (which is normal for an newly released game, sadly)
-Mostly a PvE (Player vs environment) game with a PvP (Player vs Player) mode and area sort of tacked on.
-Is a bit grindy ( at least your not paying for it, eh?)
-Some parts of the game aren't as well balanced as they could be.
-Crafting in the game is widely considered a bit of a joke and a waste of time (Hopefully will get fixed in a future patch)